Abstract

Background: Crystalloid storage histiocytosis (CSH) is a rare clinical condition characterized by abnormally high numbers of histiocytes with a large accumulation of crystalline immunoglobulins. Due to its relative rarity, clinical diagnosis of it is frequently incomplete or incorrect. We report a case with pulmonary crystal-storing histiocytosis that was mistakenly identified as lung carcinoma.
Methods: Percutaneous lung biopsy, bronchoscopy.
Results: Percutaneous lung biopsy pathology shows granulomatous inflammation with massive eosinophilic infiltration, immunohistochemistry shows CD68, kappa positive, S-100, desmin, myogenin, lambda negative. The final diagnosis is pulmonary crystal-storing histiocytosis.
Conclusions: To get pathology tissue for a definitive diagnosis, patients with pulmonary nodules who have changes in tumor markers or nodule size should have bronchoscopy or percutaneous lung biopsy done as soon as possible.

DOI: 10.7754/Clin.Lab.2024.240427